Coated and modified high-nickel ternary cathode material and preparation method thereof

Abstract

The invention discloses a coated and modified high-nickel ternary cathode material and a preparation method thereof. With a LiNi<x>Co<(1-x)/2>Mn<(1-x)/2>O<2> material as a matrix, wherein x is smaller than or equal to 0.9 and greater than or equal to 0.6; a coating layer coats the outside of the matrix; the coating layer contains a plurality of nano metal salts and/or nano metal oxides; and the total weight of cationic metal accounts for 0.01%-10% of weight of a ternary cathode material. The preparation method disclosed by the invention comprises the following steps: firstly, dissolving a soluble aluminum salt into deionized water to obtain an aluminum salt solution; adding the LiNi<x>Co<(1-x)/2>Mn<(1-x)/2>O<2> material to the aluminum salt solution for mixing evenly to obtain paste; adding an alkaline solution which is prepared from an alkaline metal compound to the paste until the pH value is greater than or equal to 7.0; and carrying out drying, sintering, natural cooling, crushing and sieving, and then obtaining the coated and modified high-nickel ternary cathode material. According to the coated and modified high-nickel ternary cathode material, the alkalinity of a high-nickel material is lowered; the coated and modified high-nickel ternary cathode material is high in processability and excellent in cycle performance and safety performance.

Description

technical field [0001] The invention belongs to the technical field of lithium-ion battery cathode materials, and in particular relates to a high-nickel ternary cathode material and a preparation method thereof. Background technique [0002] In recent years, with the rapid development of emerging demand markets such as 3C consumer electronics, power tools and electric vehicles, people have put forward higher requirements for lithium-ion batteries, requiring batteries to have high capacity, long battery life, and batteries are safe and reliable. Therefore, it is imperative to develop lithium-ion batteries with higher energy density and stable performance. LiNi x co (1-x) / 2 mn (1-x) / 2 o 2 (0.6≤x≤0.9) High-nickel ternary materials have a higher discharge specific capacity than lithium cobalt oxide materials, and have the characteristics of lower raw material costs than lithium cobalt oxide materials. Applied in conventional batteries, it can significantly increase the batt...

AI Technical Summary

Problems solved by technology

This preparation method can effectively improve the high-temperature performance of the material, but this method has undergone two liquid-phase coatings and three calcinations, and the sintering process is relatively complicated

In addition, there are other processes in the prior art that mainly select metal oxide-coated ternary materials. This method has a better effect on the stability of reinforced materials. However, due to the use of polymer polyacrylamide as a dispersant and the need for filtration , increasing the difficulty of process control and high cost

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